Allegations and counter-allegations continue to fly after yet another fish kill was recently reported in the upstream of the Periyar river in Pathalam in the south Indian State of Kerala.

The Irrigation Department and environmentalists strongly suspect industrial units situated nearby of dumping effluents in to the river leading to frequent fish kills in the area.

However, the Kerala State Pollution Control Board has stuck to its earlier claim that poor water flow in the Pathalam stretch resulted in sudden drop in the dissolved oxygen level which led to the fish kill. The Pollution Control Board had asked the Irrigation Department last week to immediately lift the shutters at Pathalam to increase the water level in the stretch.

M. S. Mythili, Chief Environmental Engineer of the board at Ernakulam, said the dissolved oxygen level at Pathalam bund was 1.6 mg/litre. She said aquatic life would be put under stress, if the oxygen level was below 2 mg/litre.

Findings rejected

A senior official of the Irrigation Department, however, has rejected the board’s findings. He pointed out that despite poor water flow in Manjummel and Purapallikavu stretches of the river, fish kills were not reported near these bunds.

“It is common sense that the industrial units near the Pathalam stretch dump toxic effluents in to the river triggering fish kills. But board officials do not confirm this as they do not want to receive the wrath of the political leadership for being anti-industry, the official said.

The Irrigation Department officials also clarified that the shutters were downed for three days after the discharge rate from Bhootatankettu dam came down considerably over the past few weeks.

Purushan Eloor, spokesperson of the Periyar Malineekarana Virudha Samithi, supported the views expressed by the Irrigation Department by stating that reduced levels of dissolved oxygen was a clear indicator of high pollution in the Pathalam stretch.

Blaming the nearby industrial units for letting untreated effluents in to the river, Mr. Purushan held the board responsible for not acting against the violators.

“According to the board the dissolved oxygen level near the Pathalam bridge where the fish kill happened is 4.7 mg/litre. This is above the minimum limit prescribed by the board, he said.

2013 The Hindu